What aggrivates me is inattentiveness.... drivers who don't signal and just drift into your lane without a thought. Drivers on cell phones. Don't stop at stop signs, or drift on through red lights.
Bicyclists who think they own the road, run red lights and stop signs, drive on the sidewalks downtown where it is illegal, or ride against traffic, use crosswalks without getting off their bikes.
Grocery store cart drivers who leave their carts in the middle of the aisle - sometimes crosswise, and are totally oblivious to their rudeness.
On the days when I have to use the store's electric scooter, this issues is 10x worse, because most grocery cart drivers don't bother to look, either. I've been hit an average of 2x per visit. Once I hit a guy who I told I was behind him coming through, he didn't pay attention and stepped right in front of me and blamed me for it. The woman next to him told him I had warned them.
I can't complain toooo much about those who interrupt while I'm talking, because I tend to do the same thing....
Hugs
Bren